Avoiding mixing overload / Re: [PD] +~?

[Larry Troxler]

On 28 Dec 2001, Andrew (Andy) W. Schmeder wrote:
> If the sample values going into [dac~] are outside of [-1, 1] then you
> are clipping the signal... (that's the soundcard clipping not the amp)
> solution; place before the dac~, [/~ n] for n = the number of signals
> you've added together.
>
>
> andy
>

Just curious about this - I've seen several times lately on various lists,
the recommendation to divide by the number of voices, but I've always
thought that if the signals aren't correlated, then scaling by the inverse
of the RMS sum of the signal amplitudes is what would result in the same
overall output level as just one signal by itself.

At least this would have to be mathematically true for white noise, would
it not?

Consider for example, mixing a full orchestra - would you really wnat
divide by the number of instruments in the orchestra? Would you then be
able to hear a solo?

My guess is that there is a tradeoff between keeping the final RMS output
the same as that of an individual signal (1/RMS-sum) vs an absolute
guarantee that there is zero chance of clipping
(1/sum-of-peak-amplitudes).

I'd love to be enlightened about this.

Larry